+# Check for a working timer_create(). We need a pretty detailed check
+# here, because there exist partially-working implementations of
+# timer_create() in certain versions of Linux (see bug #1933).
+#
+AC_DEFUN([FP_CHECK_TIMER_CREATE],
+ [AC_CACHE_CHECK([for a working timer_create(CLOCK_REALTIME)],
+ [fptools_cv_timer_create_works],
+ [AC_TRY_RUN([
+#include <stdio.h>
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+#ifdef HAVE_TIME_H
+#include <time.h>
+#endif
+#ifdef HAVE_SIGNAL_H
+#include <signal.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+static volatile int tock = 0;
+static void handler(int i)
+{
+ tock = 1;
+}
+
+static void timeout(int i)
+{
+ // timer_settime() has been known to hang, so just in case
+ // we install a 1-second timeout (see #2257)
+ exit(99);
+}
+
+int main(int argc, char *argv[])
+{
+
+ struct sigevent ev;
+ timer_t timer;
+ struct itimerspec it;
+ struct sigaction action;
+ int m,n,count = 0;
+
+ ev.sigev_notify = SIGEV_SIGNAL;
+ ev.sigev_signo = SIGVTALRM;
+
+ action.sa_handler = handler;
+ action.sa_flags = 0;
+ sigemptyset(&action.sa_mask);
+ if (sigaction(SIGVTALRM, &action, NULL) == -1) {
+ fprintf(stderr,"SIGVTALRM problem\n");
+ exit(3);
+ }
+
+ action.sa_handler = timeout;
+ action.sa_flags = 0;
+ sigemptyset(&action.sa_mask);
+ if (sigaction(SIGALRM, &action, NULL) == -1) {
+ fprintf(stderr,"SIGALRM problem\n");
+ exit(3);
+ }
+ alarm(1);
+
+ if (timer_create(CLOCK_PROCESS_CPUTIME_ID, &ev, &timer) != 0) {
+ fprintf(stderr,"No CLOCK_PROCESS_CPUTIME_ID timer\n");
+ exit(1);
+ }
+
+ it.it_value.tv_sec = 0;
+ it.it_value.tv_nsec = 1;
+ it.it_interval = it.it_value;
+ if (timer_settime(timer, 0, &it, NULL) != 0) {
+ fprintf(stderr,"settime problem\n");
+ exit(4);
+ }
+
+ tock = 0;
+
+ for(n = 3; n < 20000; n++){
+ for(m = 2; m <= n/2; m++){
+ if (!(n%m)) count++;
+ if (tock) goto out;
+ }
+ }
+out:
+
+ if (!tock) {
+ fprintf(stderr,"no CLOCK_PROCESS_CPUTIME_ID signal\n");
+ exit(5);
+ }
+
+ timer_delete(timer);
+
+ if (timer_create(CLOCK_REALTIME, &ev, &timer) != 0) {
+ fprintf(stderr,"No CLOCK_REALTIME timer\n");
+ exit(2);
+ }
+
+ it.it_value.tv_sec = 0;
+ it.it_value.tv_nsec = 1000000;
+ it.it_interval = it.it_value;
+ if (timer_settime(timer, 0, &it, NULL) != 0) {
+ fprintf(stderr,"settime problem\n");
+ exit(4);
+ }
+
+ tock = 0;
+
+ usleep(3000);
+
+ if (!tock) {
+ fprintf(stderr,"no CLOCK_REALTIME signal\n");
+ exit(5);
+ }
+
+ timer_delete(timer);
+
+ exit(0);
+}
+ ],
+ [fptools_cv_timer_create_works=yes],
+ [fptools_cv_timer_create_works=no])
+ ])
+case $fptools_cv_timer_create_works in
+ yes) AC_DEFINE([USE_TIMER_CREATE], 1,
+ [Define to 1 if we can use timer_create(CLOCK_PROCESS_CPUTIME_ID,...)]);;
+esac
+])
+
+# FP_ARG_GMP